This project is designed to provide further information on the causes of dental malocclusion in man based on experiments with the rhesus monkeys as an animal model. It is the purpose of this study to examine further how induced alterations in the mandibular postural position and movement patterns as well as lip and tongue posture and function may influence the development and shape of the facial skeleton and the postion of the teeth. The project has produced significant information on the morphogenic interaction between neuromuscular activity and bone development which can be clinically applied. It is expected that the project will provide further information which can be applied in the treatment of malformations of craniofacial structures.